updates project to work with zephyr v4.0.x (backport #146)

[mergify]

Upticks the compatible zephyr version.
The 'zephyr_library_import' needed to be replaced with 'zephyr_link_libraries' to avoid the 'whole-archive' linking behavior (which would consume massive amounts of RAM).
Other miscellaneous fixes were made in order to build.

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This is an automatic backport of pull request #146 done by Mergify.

[mergify]

Cherry-pick of 7cbe6da has failed:

On branch mergify/bp/rolling/pr-146
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Changes to be committed:
	modified:   .github/workflows/ci.yml
	modified:   README.md
	modified:   modules/libmicroros/CMakeLists.txt
	modified:   modules/libmicroros/microros_transports/serial/microros_transports.c
	modified:   prj.conf
	modified:   src/main.c

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   .github/workflows/nightly.yml

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally